As is known, the pharmaceutical industry has had limited success overcoming the challenges of delivering pharmaceuticals to patients. The oral ingestion of pharmaceuticals is considered the safest, most convenient and most economical method of drug administration. As compared to present alternatives, patient acceptance and adherence to a dosing regimen is typically higher among orally delivered pharmaceuticals. However, the oral delivery of many pharmaceuticals is not possible because the pharmaceuticals are either too large or too electrically charged to pass through the small intestine to reach the bloodstream. In addition, many pharmaceuticals that are unable to withstand the environment of the digestive tract or to penetrate the dermis need to be injected into the patient (e.g. insulin, proteins). As hereinafter described, the injection of pharmaceuticals into a patient has certain drawbacks.
By way of example, insulin is often used to treat diabetes, a disorder of metabolism. Most of the foods eaten by individuals are broken down in the body into glucose, the form of sugar in the blood. Glucose is the main source of fuel for the body. After digestion, the glucose passes into the bloodstream where it is used by the cells for growth and energy. For glucose to get into cells, insulin must be present. Insulin is a hormone that is automatically produced by a healthy pancreas to move glucose from blood into our cells. In people with diabetes, however, the pancreas either produces little or no insulin, or the cells do not respond appropriately to the insulin that is produced. As a result, glucose builds up in the blood, overflows into the urine, and passes out of the body. Consequently, the body loses its main source of fuel, even though the blood contains large amounts of glucose.
In order to use the glucose present in the body, a diabetic must take insulin injections every day. The amount of insulin taken by an individual must be balanced with the individual's food intake and daily activities. Consequently, blood glucose levels must be closely monitored through frequent blood glucose checking to insure that blood glucose levels do not fall too low or rise too high. When blood glucose levels drop too low from certain diabetes medicines—a condition known as hypoglycemia—a person can become nervous, shaky, and confused. If blood glucose falls, judgment can be impaired and a person could faint. Alternatively, a person can also become ill if blood glucose levels rise too high, a condition known as hyperglycemia. Although daily insulin injections are a great inconvenience, they are necessary for a diabetics' survival.
Most people with diabetes administer their own insulin after learning the proper techniques for insulin preparation and injection. The goal of insulin administration is to give enough insulin to cover the amount of food (especially carbohydrates) that a person consumes so that blood glucose levels remain normal throughout the day and night. It can be appreciated that various factors such as the type of insulin used, the size of the person, the amount, type, and time that meals are eaten, and the activity and exercise patterns of the person effect the amount of insulin that is required by an individual. It takes a dedicated patient to continually monitor their blood glucose level and administer the repeated multiple injections required. Therefore, an autonomous infusion system that provides a steady infusion of pharmaceuticals to an individual when needed would constitute a significant advancement in the art.
Therefore, it is a primary object and feature of the present invention to provide a microfluidic device that delivers a steady infusion of pharmaceuticals to an individual when needed.
It is a further object and feature of the present invention to provide a microfluidic device that delivers a steady infusion of pharmaceuticals to an individual under autonomous control.
It is a still further object and feature of the present invention to provide a microfluidic device for delivering a steady infusion of pharmaceuticals to an individual that is simple to utilize and inexpensive to manufacture.
In accordance with the present invention, a microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a reservoir for receiving a drug therein and an output needle. The output needle has an input in communication with the reservoir and an output receivable within the individual. A pressure source is engageable with the reservoir for urging the drug from the reservoir through the output needle.
The microfluidic device includes a flexible membrane isolating the pressure source from the reservoir. A valve operatively connects the input of the output needle and the reservoir. The valve defines a chamber having an input communicating with the reservoir and an output communicating with the input of the output needle. The valve also includes a flexible membrane dividing the chamber into a first drug flow portion and a second trigger receiving portion. A trigger is disposed in the trigger receiving portion in the chamber of the valve. The trigger has a first configuration preventing the flow of the drug through the chamber and a second configuration allowing for the flow of the drug through the chamber.
A first sensing needle has an input receivable in the individual and an output within the trigger receiving portion of the chamber. The first sensing needle allows physiological fluids to pass from the individual to the trigger receiving portion of the chamber. A second sensing needle may also be provided. The second sensing needle has an input receivable in the individual and an output within the trigger receiving portion of the chamber. The second sensing needle allows physiological fluids to pass from the individual to the trigger receiving portion of the chamber in the valve. It is contemplated for the trigger to include a hydrogel post that is expandable in response to exposure to a predetermined condition in the physiological fluid. Hydrogels are stimuli crosslinked polymeric materials that change their state of swelling, as manifested by a change in size, in response to chemical and physical changes in their surrounding environment. It is contemplated for the hydrogel post to be formed entirely from a hydrogel material or to be formed from a solid post having the hydrogel material formed thereabout.
The microfluidic device also may include a second reservoir for receiving a bolus of the drug therein. An actuation device is also provided. The actuation device is movable between a non-actuated position and an actuated position wherein the bolus of the drug is urged through the outlet needle and into the individual.
In accordance with a further aspect of the present invention, a microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein and a conduit. The conduit has an input communicating with the reservoir and an output. An output needle has an input receivable in the body to communicate with the output of the conduit and an output outside of the body for insertion into the individual. A pressure source is engageable with the reservoir for urging the drug from the reservoir through the output needle.
It is contemplated that the output needle be removable from the body. In addition, it is contemplated that a flexible membrane isolate the pressure source from the reservoir. The conduit may include a valve for controlling the flow of the drug from the reservoir to the output needle. The valve defines a valve chamber and is movable between a non-actuated position wherein the valve prevents the flow of the drug from the reservoir to the output needle and an actuated position wherein the valve allows for the flow of the drug from the reservoir to the output needle. A flexible membrane divides the valve chamber into a first drug flow portion and a second trigger receiving portion. A trigger is disposed in a trigger receiving portion of the valve chamber. The trigger has a first configuration with the valve in the non-actuated position and a second configuration with the valve in the actuated position. A first sensing needle has an input receivable in the individual and an output within the trigger receiving portion of the valve chamber. The first sensing needle allows physiological fluids to pass from the individual to the trigger receiving portion of the valve chamber. The trigger includes a hydrogel post. The hydrogel post changes the configuration in a response to exposure to a predetermined condition in the physiological fluids.
The body may also define a second reservoir for receiving a bolus of the drug therein. An actuation device is also provided. The actuation device moves between a non-actuated position and an actuated position wherein the bolus of the drug is urged from the second reservoir; through the outlet needle; and into the individual.
In accordance with a still further aspect of the present invention, a microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body defining a reservoir for receiving the drug and an output needle. The output needle has an input in communication with the reservoir and an output receivable within the individual. An adhesive is provided for affixing the body to the individual.
The microfluidic device may also include a pressure source engageable with the reservoir for urging the drug from the reservoir through the output needle. A docketing station supports the output needle. The docketing station is removably connected to the body. A valve defining a chamber interconnects the reservoir and the output needle. The valve is movable between a non-actuated position wherein the valve prevents the flow of the drug from the reservoir to the output needle and an actuated position wherein the valve allows for the flow of the drug from the reservoir to the output needle. The valve includes a flexible membrane for dividing the valve chamber into a first drug flow portion and a second trigger receiving portion. A trigger is positioned within the trigger receiving portion of the valve chamber. The trigger has a first configuration with the valve in a non-actuated position and a second configuration with the valve in the actuated position. A first sensing needle has an input receivable in the individual and an output within the trigger receiving portion of the valve chamber. The first sensing needle allows physiological fluids to pass from the individual to the trigger receiving portion of the valve chamber. The trigger may include a hydrogel post that changes configuration in response to exposure to a predetermined condition in the physiological fluids.
The body may also define a second reservoir for receiving a bolus of the drug therein. An actuation device is also provided. The actuation device is movable between a non-actuated position and an actuated position wherein the bolus of the drug is urged from the second reservoir, through the outlet needle, and into the individual.